Liquid crystal display devices are in widespread use at present, in various types of equipment. In order to display, for example, numeric data comprising a fixed set of numerics located in predetermined positions, it has been common practice to provide a group of seven display segments, each of which can be independently activated. Such an arrangement enables numerics to be displayed with a relatively small number of interconnecting leads between the liquid crystal display device and the peripheral circuitry which supplies drive signals to excite the display segments. However, this type of display device has the disadvantage of a lack of flexibility. For example, the groups of segments cannot be used to display either numerics or alphabetic characters, as required. In addition, it is not possible to change the position of a numeric or other symbol in a smooth and continuous manner, or to change the size of such a symbol or numeric. Another type of liquid crystal display device is of the dot matrix type. With such a display device, individual "dots" can be independently excited into visibility, by means of signals applied to a set of row and column common electrodes. This type of display device enables numerics, symbols, etc, to be formed anywhere on the display matrix, and to be varied in size and position in a completely free and independent manner. However, it has the disadvantage that the number of interconnecting leads required between the display device and the peripheral drive circuitry is considerably larger than for the first type of display device described above. This is due to the fact that with, for example, a 7-segment type of display arrangement, advantage is taken of the fact that the number of shapes which must be displayed to indicate the various numerics of other symbols is limited, so that by using display segments of a particular shape (generally rectangular) and positioned in a predetermined manner, it becomes necessary to provide only a relatively few interconnecting leads.
There is therefore a requirement for a liquid crystal display device which will provide the advantages of freedom is positioning numerics, alphabetics, etc, capability for changing the sizes of such characters, yet which will not require the large number of interconnecting leads which are necessary with a conventionaly type of dot matrix display device. These requirements are met by a liquid crystal display device according to the present invention.